[0001] The present invention relates to a facsimile apparatus. It also relates to a method
of processing a document by such a facsimile apparatus, by e.g. either transmitting
an image of the document to a remote location, or copying an image on the document,
as appropriate.
[0002] In a standard facsimile apparatus, a document to be transmitted is moved past a fixed
reading device, and an image signal generated corresponding to the image on the document
(whether words or graphics). That image signal may then be transmitted to a remote
location e.g. via the telephone network, or maybe used to reproduce the image on material
(normally papers) withdrawn from a roll thereof. In a similar way, an image signal
of a document received by the facsimile apparatus via the telephone network from a
remote location may be printed on the material withdrawn from the roll.
[0003] In such a conventional facsimile apparatus, it is not possible for the facsimile
apparatus to scan documents other than in sheet form, because the document must be
moved passed the reading device, and in practice this is normally achieved by drawing
the document sheet through a nip between rotating rollers. Thus, it is not possible
for a conventional facsimile apparatus to transmit a page of a bound book. If such
a page is to be transmitted, it must first be copied by a suitable copying apparatus
onto a sheet, so that sheet can be transmitted. Therefore, facsimile apparatuses have
been developed in which a scanning means is movable relative to a transparent plate
which can receive the document thereon. Thus, a page of a bound book may be placed
on the transparent plate, and the scanning means operated. The scanning means then
moves relative to the transparent plate to generate the image signal. Of course, such
a facsimile apparatus may also transmit an image from a document in sheet form, by
placing the sheet on the transparent plate. Examples of such facsimile apparatuses
are shown in JP-A-60-118553, JP-A-60-232345, JP-63-117851, and JP-A-2-174362.
[0004] Another feature of conventional facsimile apparatuses is that they print onto material
(normally paper) which is withdrawn from a roll. Therefore, the user must buy special
paper for the facsimile apparatus, and cannot use plain paper sheets which are more
readily available. Therefore, facsimile apparatuses have been proposed in which plain
paper sheets are used.
[0005] One existing facsimile apparatus, the Fuji Xerox ABLE 3015 facsimile apparatus, combines
both of the developments discussed above. In that facsimile apparatus, there are two
reading modes, by which a document is scanned. Firstly, a document in sheet form can
be scanned in the normal way, by moving the sheet past suitable scanning means. secondly,
a document in book or sheet form may be placed on a transparent plate and scanned.
Printing of images occurs on cut sheets, making use of laser printer technology. The
resulting apparatus is large and expensive.
[0006] An article entitled "Image Scanning Control Method for Accommodation Type Sensor",
published in IBM Technical Disclosure Bulletin, Vol. 29, No. 5, October 1986 page
2253, discussed a scanner in which a solid state light generation means in the form
of an LED was used. The LED was controlled to ensure that the exposure time remained
constant for each scan cycle. To achieve this, the LED was continuously energised
when the speed of scanning was constant, but was operated intermittently during acceleration
and deceleration. The aim of this was to present saturation of the light sensor.
[0007] According to the present invention there is provided a facsimile apparatus, comprising:
a transparent plate for receiving a document to be processed;
scanning means movable relative to said transparent plate for scanning said transparent
plate as a plurality of sequential lines so as to generate a signal corresponding
to an image on said document;
output means for selectably transmitting said signal to a remote destination;
input means for receiving a further signal representing a further image from a remote
origin;
store means for storing material for printing thereon, said material being in the
form of a plurality of sheets; and
printing means for withdrawing at least one sheet from said store means, receiving
at least one of said signal and said further signal, and printing on said at least
one sheet, sand printing on said sheet being a representation of at least one of said
image and said further image;
wherein:
said scanning means includes electronic solid state light generation means in the
form of an LED light source for generating light for illuminating said transparent
plate and detector means for detecting reflected light through said transparent plate
and generating said signal therefrom, wherein the solid state light generation means
is connected to a DC voltage via light control means, the light control means including
a switching means (Q1) and means for generating pulses for controlling the switching
means (Q1) such that the solid state generation means is caused to pulse a plurality
of times during each sequential line.
[0008] Use of such electronic solid state light generation means within the present invention
provides a number of advantages. Firstly, it is relatively simple to control the quantity
of light generated by such solid state light generation means, and such control is
preferably on the basis of a pulse signal, so that pulsed light is generated. The
pulse rate of those pulses may then be controlled to give different effects. For example,
the speed of scanning of the document may depend on the quality of the telephone line
by which the electronic signal representing the image on the document is to be transmitted,
or the degree of fineness of the resulting image. However, if the amount of light
is held constant, it is possible for the detector detecting the light to become saturated
when the speed of the document is low. By using a pulsed signal to the solid state
light generating means, the pulse rate can be varied depending on the transmitting
speed. Indeed, it is then particularly advantageous if the pulse speed is synchronised
with the speed of movement of the scanning means relative to the transparent plate
on which the document is located. It is also possible, by varying the pulse rate,
to achieve scaling (changing the size of the final image relative to the original
image).
[0009] Embodiments of the present invention will now be described in detail, by way of example,
with reference to the accompanying drawings in which:
Fig. 1a shows a general perspective view of a facsimile apparatus according to a first
embodiment of the present invention;
Fig. 1b shows a sectional view through the facsimile apparatus of Fig. 1a;
Fig. 1c shows a modification of the facsimile apparatus of Fig. 1a;
Figs. 2a and 2b are views from above and below respectively of a cassette for an ink-carrying
film;
Figs. 3(1) to (6) are block diagrams showing data flows within a facsimile apparatus
according to the present invention;
Fig. 5 illustrates schematically an example of the assignment of memory addresses;
Fig. 6 is an example of an indicator display for indicating internal states of the
facsimile apparatus;
Fig. 7 shows schematically the reading of documents by the apparatus of Fig. 1c;
Fig. 8 shows the configuration of an image data processing unit;
Fig. 9 shows signal timings in the image data processing unit of Fig. 8;
Fig. 10 illustrates image transmission;
Fig. 11 shows schematically a document reading operation of a facsimile apparatus
according to the present invention;
Fig. 12 illustrates the transmission of similar images according to the present invention;
Fig. 13 is a block diagram showing processor processing operations;
Fig. 14 is a chart showing transition states;
Fig. 15 is a block diagram showing part of the facsimile apparatus according to the
present invention;
Fig. 16 is a block diagram showing a further part of the facsimile apparatus according
to the present invention;
Fig. 17 shows a modification of the part of the facsimile apparatus of Fig. 16;
Fig. 18 illustrates schematically documents scanning in an embodiment of the present
invention;
Fig. 19 illustrates further the scanning operation;
Fig. 20 is a flowchart of the scanning operation;
Fig. 21 is a further flowchart of the start of the scanning operation;
Fig. 22 is a flowchart showing the storage of information in a facsimile apparatus
according to the present invention;
Fig. 23 is a further flowchart showing the operation of a facsimile apparatus according
to the present invention;
Fig. 24 illustrates the relationship between motor speed and data collection at one
reading pitch;
Fig. 25 shows the relationship between motor speed and data collection at a second
reading pitch;
Fig. 26 shows the relationship between the motor speed and data collection at a third
reading pitch;
Fig. 27 illustrates the relationship between motor pulses and reading control;
Fig. 28 illustrates a part of the control means for the solid state light source of
an embodiment of the present invention;
Fig. 29 illustrates motor speed pulses at one reading pitch;
Fig. 30 shows motor speed pulses at a second reading pitch;
Fig. 31 also illustrates motor speed pulses.
[0010] Fig. 1(a) shows a general perspective view of a facsimile apparatus in which the
present invention may be embodied. The facsimile apparatus shown in Fig. 1 has a body
10 having a transparent plate 11 in a surface thereof, on which plate 11 a document
to be scanned may be placed. Fig. 1(a) also shows a lid 12 of the apparatus, to reduce
the amount of stray light reaching the transparent plate 11, and controls 13 (shown
schematically) for operating the facsimile apparatus.
[0011] A cross-sectional view of the facsimile apparatus of Fig. 1(a) is shown in Fig. 1(b).
It can be seen that the body 10 comprises upper and lower body parts 20, 21 which
are separable to permit access to the interior of the body 10. The lower body part
21 receives therein a store 22 for storing therein sheets of paper on which images
are to be printed by the facsimile apparatus. The lower body part 21 also supports
therein a cassette 23 containing a film 24 carrying ink. Heating means 25 is controlled
so as to establish a heating pattern which transfers ink from the film 24. In the
printing operation, a paper sheet is withdrawn from the store 22 via a roller 26,
and passed between the film 24 and a further roller 27 below the heating means 25.
That heating means 25 then heats the ink in the desired pattern corresponding to the
image, so that the image is then transferred to the paper sheet. The paper sheet is
then guided via a guide 28 to the upper surface 29 of the store 22, so that the space
30 above that store 22 acts as a sheet receiving tray. Thus, the printed sheets are
received within the body 10 of the apparatus, rather than on a projecting tray.
[0012] The upper part 12 of the body 10 of the apparatus has a scanner 31 including a linear
arrangement of LEDs 32 and a light detector 33. The scanner 31 is movable below the
transparent plate 11 along a track 33. In this way, a document placed on the transparent
plate 11 may be scanned on the basis of illumination from the LEDs 32, and the resulting
image detected by the detector 33.
[0013] Fig. 1(c) illustrates a modification of the facsimile apparatus of Figs. 1(a) and
1(b). In the embodiment of Figs. 1(a) and 1(b), a document is placed on the transparent
plate 11 and the scanner 31 moves to scan the image thereon. In the embodiment of
Fig. 1(c), it is also possible to scan a document in sheet form with the scanner 31
fixed. In the embodiment of Fig. 1(c), an upper surface 40 of the lid 12 has a paper
guide 41 which guides a paper sheet into an aperture 42, where it is engaged between
a plate 43 and a roller 44. That guides the sheet between rollers 45, 46 and down
a track 47 so that it passes above the scanner 31 and hence may be illuminated by
the LEDs 32. Rollers 48, 49 then guide the sheet from under the lid 12. This operation
will be discussed in more detail later. The part 50 of the lid above the channel 47
may be hinged about hinge 51 to permit it to be listed in the direction of arrow 52
to permit access to a sheet in the channel 47 if, for example, there is a paper jam.
[0014] The apparatus shown in Figs. 1(a) to 1(c) has several operation modes. These will
now be discussed in more detail.
(1) Image reading
[0015] The image reading section has image data to be transmitted to a destination party
through transmission line. Image reading occurs in either of the following two modes
of operation.
a) A book reading mode in which that the document is put on the transparent plate
19, and sensor scanning is made as the document and the sensor are moved relative
to each other.
b) A sheet reading mode in which the sensor is fixed, and sensor scanning occurs as
the document is moved.
[0016] The facsimile function is not restricted by those modes of operation, but the former
book reading mode of operation allows a thick book to be input directly while the
latter sheet reading mode allows a plurality of sheets to be read continuously and
automatically when an automatic sheet feeding unit is combined therewith. As the two
modes of operation have respective advantages, users may select the appropriate mode
of operation as desired. The embodiment shown in Fig. 1c permits the lid of the facsimile
apparatus to have a configuration that allows for the both modes of operation so that
a variety of documents can be read.
[0017] The two image reading modes can use either an independent sensor for each mode or
a common sensor. With the common sensor, for example, in the book reading mode, the
sensor is moved below the transparent plate and in the sheet reading mode an arrangement
is provided so that the sheet can be moved above the sensor, which is fixed at an
end of the transparent plate.
[0018] The image reading section can have a document reading mode selecting arrangement
provided therefor, e.g. in the controls 13. Depending on a suitable set value signal
processing occurs to select a desired image reading mode. The sensor can be moved
to its initial position depending on the set value.
(2) Recording
[0019] Recording section for a facsimile receiving image or copying image is not restricted
to a specific method. However, the present embodiment may make use of, for example,
a heat sensing recording method, a heat sensing transfer method, and a toner developing
method. In the heat sensing transfer method, as an example, ink coated on afilm is
selectively heated by a heat sensing head so that it is transferred to plain paper.
[0020] If the ink on the film is arranged so that it cannot all transferred be transferred
at once, the ink film can be used a plurality of times. It is relatively rare that
the whole sheet has an image recorded therein. Thus, the decrease in ink concentration
when a plurality of recordings are made is lowered if recording parts are not completely
aligned every time. This is advantageous to minimize consumption of the ink film.
[0021] Figs. 2a and 2b show in more detail the structure of the cartridge 23. As shown in
Figs. 2a and 2b, the cartridge 23 has a pair of shafts 60, 61 around which is wrapped
the film 24, so that the film 24 extends across an opening 62 in an upper surface
63 of the cassette 23, through which the heating means 25 will be moved to contact
the film 24. Each of the shafts 60, 61 terminates in a drive wheel 64, 65 respectively.
When the cassette is in the position shown e.g. in Fig. 2a, the drive wheel 64 of
the shaft 61 may engage with a suitable drive to draw the film 24 from the shaft 61
to the shaft 62. When the end of the film 24 is reached, the cassette 23 can be rotated
through 180° about axis 66, so that the drive wheel 65 of the shaft 61 is now driven,
to cause the film 24 to move from the shaft 60 to the shaft 61. Thus, it is possible
by rotating the cassette to achieve a multiplicity of operating runs of the film from
one shaft to the other. It is also possible, of course, to provide drives to each
of the wheels 64, 65 so that the direction of movement of the films 24 can be reversed
without movement of the cassette 23.
(3) Transmission control
[0022] In order to make facsimile communication through an analog telephone network, transmission
control procedures are executed, which comply with the standard of Group 3 facsimiles
recommended by the CCITT (International Telegraph and Telephone Consultative Committee).
[0023] The telephone number of the destination party can be entered without installation
of an additional telephone dialling feature on the facsimile apparatus according to
the present invention, by use of a telephone set connected to the facsimile apparatus
in a master-slave relationship.
[0024] Also, a list of the telephone numbers of destination parties used often can be stored
in the facsimile apparatus or as an IC card which is portable.
[0025] An example of a control circuit to accomplish the facsimile apparatus discussed above,
is shown in Fig. 3.
[0026] The data flow corresponding to the facsimile features will now be described with
reference to the circuit construction shown in Fig. 3. Fig. 3 shows an image data
input reading arrangement 1110 for input of image data, a pre-processing arrangement
1120 for the input image data, which is referred to as facsimile video processor (FVP)
recording arrangement 1130 for the image data, an exclusive OSI 1140 for executing
the facsimile signal process, which is also referred to as a system control ASIC (SCA),
a central processing unit (CPU) 1150 or a microprocessing unit (MPU), and a read only
memory ROM 1160 for storing programs for the CPU 1150.
[0027] Also, Fig. 3 shows a line memory LM 1170, a line memory BM 1180, and a page memory
PM 1190 which provide different functions for storing the image data, code data, and
one page image data, respectively.
[0028] Fig. 3 shows a modulation/demodulation unit modem 1200
for input or output of signals via an external analog telephone line.
[0029] The following describes data flow for use of the facsimile apparatus described above
for (1) instantaneous transmission, (2) instantaneous reception, (3) copying, (4)
memory storage, (5) memory transmission, and (6) memory reception. The data flows
are indicated by arrows in Fig. 3.
(1) Instantaneous transmission
[0030] In data flow *1, the image data entered through the image data input reading arrangement
1110 is pre-processed, such as by shading correction, by the pre-processing arrangement
1120, and then is transferred to the line memory LM 1170 in a DMA (direct memory access)
way.
[0031] In data flows *2 and *3, data, stored in the line memory LM 1170 including the present
line PL to be encoded and a reference line LL to be referred to for encoding, are
transferred to the OSI 1140, which in turn generates data for generation of coded
words on the basis of picture element positions in the PL and LL. It should be noted
that the algorithm used for encoding process complies with the CCITT recommended modified
Halfmann (MH), modified read (MR), or modified (MMR) systems.
[0032] In data flow *4, the CPU 1150 creates the coded word, on the basis of the data generated
in the OSI 1140 for generation of coded words, which in turn is transferred to the
OSI 1140.
[0033] In data flow *5, as since the coded word is generally a bit stream of fixed length,
the OSI 1140 can write it in the line memory BM 1180 when a number, for example, eight,
bits, are collected.
[0034] In data flow *6, in turn, data is transferred from the transmission/reception line
memory BM 1180 to the modem 1200 in time with signal transmission of the modem 1200.
(2) Instantaneous reception
[0035] In data flow *7, the signal input from an external analog line is converted to a
digital signal by the modem 1200. The digital signal then is written in the transmission/reception
line memory BM 1180.
[0036] In data flow *8, data in the transmission/reception line memory BM 1180 is transferred
to the OSI 1140, which in turn generates data for code detection suitable for the
decoding process.
[0037] In data flow *9, the data is-transferred to the CPU 1150. The CPU 1150 re-stores
the image data so that it is stored in the line memory LM 1170 while compares it with
the decoded data in the reference line (data line *2).
[0038] In data flow *11, the image data obtained as described above is transferred to the
recording arrangement 1130, which reproduces the recording image.
(3) Copying
[0039] The image data input through the image data input reading arrangement 1110 is pre-processed
by the pre-processing arrangement 1120, and then is stored in the line memory LM 1170.
The image data is transferred from the line memory LM 1170 to the recording arrangement
1130, which reproduce the recording image.
(4) Memory storage
[0040] The coded word is generated in the same way as in instantaneous transmission. The
generated coded word is not output from the modem 1200, but is stored in the page
memory PM 1190.
(5) Memory transmission
[0041] In order to transmit the coded words stored in the page memory PM 1190 to a destination
party, those words are converted to an image size specific to the recording capacity
of the destination machine. The converted signal is output through the modem 1200.
[0042] For this purpose, data transference is made for the image size conversion using the
CPU 1150 and the OSI 1140 (data flows *13 and *14). The generated coded words are
transferred to the transmission/reception line memory BM 1180 and fed out through
the modem 1200.
(6) Memory reception
[0043] The received data is not decoded, but the received data in the transmission/reception
line memory BM 1180 is stored in the page memory PM 1190 in units of one page. The
data are encoded and processed to reproduce recorded image as necessary.
[0044] In turn, the software for accomplishing the above operations of the facsimile apparatus
can be structured as shown in Fig. 4 as an example. It has a hierarchic structure
with an overall control section for controlling the entire system, individual control
sections for controlling individual features, task and subtask sections for processing
signals which are controlled by the individual control sections, and a device driver
section for controlling features specific to devices. Every feature is in the form
of a module, which facilitates program correction and addition and program development
and debugging.
[0045] The execution procedures of each program can be described as a combination of the
current state with a future event. They can be controlled by the overall control section
so that each of the lower levels can have its program described independent of the
whole system.
[0046] To control the facsimile apparatus, for example, an eight bit CPU can be used so
that the address space is region and can be designated with a 16 bit binary signal.
It is however desirable that the address space has a program memory, image data, and
code data superimposed thereon, as programming is often restricted.
[0047] To avoid such a difficulty, the address space may have a plurality of numbered memories
assigned in the same region so that the number designation can be executed independently
in parallel with the address designation. This can make the memory region be physically
greater than the address space that the CPU can designate directly.
[0048] Fig. 5 shows an example of the assignment of memory addresses arranged in the way
described above. The memory numbers mentioned above correspond to divided features
of the software so that, for example, the memories can be used for image memory, but
not for code memory. This means that the physical memory can be made functionally
clear for use.
[0049] The divided memory described above facilitates correction, addition, and debugging
during creation of the program. It also makes clear the functions corresponding to
specific features, for example, the addition of memory capacity to be used as optional
feature. Thus, it is greatly advantageous in constructing the apparatus.
[0050] It is very important that an operator is aware of the facsimile features and operational
states for smooth operation and prevention of erroneous operation. For the purpose,
the apparatus can include features for indicating character information or generatinging
out voice information.
[0051] However, it is also important to make the construction of the apparatus as simple
as possible. Fig. 6 shows a seven segment indicator, as an example, which gives information
to the operator. Such an indicator may form one of the controls 13. The simple indicator
can indicate to the operator not only transmitting and receiving details characteristic
to the facsimile operation, but also facsimile states, including set quantity of copyies
reporting communication control, passing error messages such as jamming of recording
paper, and other information.
[0052] The indicator is useful to simplify the apparatus and clearly indicate to the operator
the operational states.
[0053] As described previously, entering an image of document can be made in either of the
following two modes of operation.
a) A book reading mode.
b) A sheet reading mode.
[0054] When both document reading modes are available, they may be sequentially or selectively
usable by means of, for example, a selection button.
[0055] Fig. 7 shows a combination of both document reading modes of operation which allows
for the following operations. A book reading plate (transparent plate 19) should have
a document for facsimile transmission, and the sheet reading section should have a
sheet containing a destination telephone number of, for example, OCR (optical code
readable) form described and provided at a plurality of positions. Several of the
OCR sheets may be available.
[0056] Firstly, at least one destination telephone number is entered via the sheet reading
section. Secondly, the document on the book reading table (transparent plate 19) scanned
to transmit coded data to the destination party. Thirdly, the designated telephone
number should be re-entered on the sheet reading section so that facsimile transmission
can be made in the book reading mode.
[0057] With the procedure described above repeated, the image data of the document to be
sent can be code transmitted while sensor scanning occurs. This allows the same image
data to be transmitted to a plurality of destination parties without image data being
stored in a memory of the apparatus.
[0058] Similarly, to copy the document on the book reading table (transparent plate) to
a plurality of sheets sensor scanning should be repeated a plurality of times. This
can be executed without storing image data in the memory.
[0059] It should be noted that sensor scanning repeated a plurality of times, is not be
limited in a direction, but may be in any of lateral direction.
[0060] It is sometimes desirable that the size of the image read by scanning should be magnified
or reduced before being code transmitted. This happens when the procedures for checking
the capabilities of both communication parties are executed and on the basis of the
result, the transmitting party has to convert the image size so that it coincides
with the image size available to the receiving party. Image size magnifying and reducing
is not be limited to one method, but may be executed by hardware or software or a
combination of both.
[0061] Fig. 8 is an example of an image data processing unit for magnifying or reducing
(scaling) the image size. The image data processing unit comprises an external interface
circuit 1500 for controlling signals between an external bus and an internal bus,
a bus timing control circuit 1501 for managing the bus controlling signals, a multi-dimensional
address generating circuit 1502 for converting between addresses in a two-dimensional
image plane and addresses in a memory arranged in one dimensional fashion and for
controlling bit arrangement of single picture element, a plurality of color signals
for a color image, a buffer memory 1503 for storing image data, an arithmetic circuit
1504 for executing signals using of the image data in the buffer memory 1503, a control
register 1505 and a program memory 1506 for setting operation conditions of the image
data processing unit using of the external CPU, and a control circuit 1507 for executing
and operating the above mentioned component circuits of the image data processing
unit.
[0062] The image data processing unit is connected to e.g. the CPU, and the image memory,
through the bus so that it can operate sequentially according to values registered
by the CPU and an internal program to input or output data from the image memory.
Bus access is made so as to avoid data collision with other units capable of bus accessing
the bus. The data stored in the internal buffer memory 1503 can be processed by the
arithmetic circuit 1504 for e.g. magnification, reduction, rotation, filtering and/or
level conversion. The internal buffer memory 1503 can be doubled, one part for executing
data input and output and the other part for arithmetic processing, thereby shortening
the execution and processing time. Fig. 9 is a timing chart for signal processing
of the image data processing unit.
[0063] As described above, the image data processing unit has an image memory and an arithmetic
circuit in addition to the features of a data transfer unit conventionally know as
direct memory access controller (DMAC). It has the great advantage that it can execute
at a high speed the input and output of the image data of the address arrangement,
related to the image composition as well as magnification, reduction, filtering, and
other arithmetic processes based on image composition, without increasing the load
on the CPU. It also has another great advantage in that the unit can be constructed
simply.
[0064] Fig. 10 illustrates a two-dimensional source image and a destination image for signal
processing of parts of the image. The multi-dimensional address generating circuit
1502 is used to define actual memory addresses. The generation of the memory addresses
can be made by distinguishing a plurality of color signals of the color image, the
bit width per picture element, horizontal or vertical subsampling, and/or other set
values. This has the advantage of decreasing the load on the CPU.
[0065] In order to encode and code process a multi-value image in which a single picture
element is represented by a plurality of bits, using e.g an orthogonal conversion,
such as a discrete cosine conversion, it data should be input or output in signal
processing units of, for example, 8 by 8 picture elements. The multi-dimensional address
generating circuit 1502 can execute data transfer sequentially in units of a two-dimensional
image block of 8 by 8 picture elements at a high speed, with no duplication or omission
of picture elements between the blocks without increasing the load on the CPU, and
maintaining the scanning order of the block units.
[0066] The internal arithmetic circuit 1504 can have an additional multiplier circuit and
an adder circuit, suitable for orthogonal conversion, to control the arithmetic order
so that the orthogonal conversion can be executed at a high speed.
[0067] The scanner section of the facsimile apparatus may be constructed so that it can
read in a block fashion, as shown in Fig. 11. This allows picture element data to
be input repeatedy while the sensor scannes the same document a plurality of times.
This feature is not available in a conventional sheet reading mode.
[0068] The probility of a plurality of sensor scans allows signal processing by: (i) judgement
of the document size, (ii) judgement of character areas, drawing areas, and similar
areas through signal processing of the image data on the document, and (iii) signal
processing for calculating statistical signal values of the whole image, permitting
signal processing to improve the image quality.
[0069] The sensor scanning may be either to the right or to the left in the figure, and
is not limited to a single direction.
[0070] Fig. 12 is block diagram illustrating connection with a destination party. In Fig
12, in order to connect a facsimile apparatus, such as one of CCITT Group 3 which
assumes an analog telephone network, with a digital network, to transfer data between
it and another facsimile apparatus having digital capabilities, a protocol converter
called a terminal adapter (TA) has to be inserted therebetween. The TA is needed to
provide an interconnection capability according to the standard of the facsimile communication
through the digital network. However, if the features of the destination facsimile
apparatus can be uniquely specified with a telephone number of the digital network,
the facsimile apparatus does not always have to comply with the communication standard,
but can make data transfer using its own control procedures. In this case, the facsimile
communication can be acheived by specifying the destination telephone number and features
to be used before the coded data in a Group 3 facsimile apparatus is directly transmitted
in digital fashion without conversion to an analog signal by a modem. Specifying the
destination telephone number as may determined which whether the communication standard
or the internal control procedures should be used.
[0071] Thus, the facsimile apparatus or an IC card held by an operator can have a list of
destination telephone numbers, corresponding features for example, analog or digital
capability and highest communication speed preset therein. This allows omission of
parts of the checking procedures of the capabilities of the two parties specified
in the communication standard for the destination parties listed. It also allows determination
of availability of the own control procedures are available. In this way, it is possible
to shorten or omit the time for the communication controls other than those of the
image data transfer. This is advantageous in that the time needed for the facsimile
communication can be shortened.
[0072] Alternatively, for signal processing on the receiving side, a receiver can have a
plurality of telephone numbers assigned thereto. The capabilities of the apparatus
transmitting may be determined in dependence on the called telephone number, so as
to determine whether connection is made by the communication standard or by the internal
control procedures.
[0073] In general, conditions which the signal process procedures for the CPU are determined
can be those of combination of the present state with events allowed in the present
state. Depending on the conditions, the signal processing procedures to be executed
and the subsequent state can be determined.
[0074] Such operations of the CPU are described in a program language as shown in Fig. 13(1),
and are stored in the program memory so that they can be set.
[0075] However, the description of the CPU operation in the program language may cause problems.
Examples of these include (1) unclear conditions for the combination of the state
with events, which result in difficulties in program correction, addition, and for
debugging, and (2) significant ranges to be checked due to addition of a new optional
feature.
[0076] To avoid such problems and describe the signal processing procedures clearly, use
may be made of a technique called the state transition table which charts the signal
processing procedures to be executed in the combination of the state with the event
and the change to the next state. The state transitions are given in, for example,
the CCITT recommendation in which the transmission control procedures are specified.
[0077] Thus, the CPU operation is set by the above mentioned state transition table as shown
in Fig. 13(2) rather than described in the program language. This allows control of
the state transition of the apparatus to be distinguished from CPU operation under
controlled conditions. Thus, for example, the decision to comply with the communication
standard is made using of the state transition, while the communication processing
procedures are characteristic to the apparatus. This has the advantage that program
correction, addition, and/or debugging, can be made easily.
[0078] However, in general, not all the combinations of the states in the state transition
table are possible, but there are many ineffective combinations. For this reason,
as shown in Fig. 14, the state transition table has blanks therein for which contents
are not described.
[0079] It is not always possible, due to use of the memory that such a state transition
table is stored unchanged in the memory. To solve this, as shown in Fig. 13(3), there
may be an additional data compression/expansion feature capable of data compression
or expansion for the state transition table. It can compress the data when it is stored
in the memory, and expand it when it is needed for the CPU operation. In other words,
the data can be in the memory in a form in which it can be referred to by the CPU
so that the efficiency of memory can be improved.
[0080] If the state transition table is determined to be little related to the CPU operation
in the current state, the data is controlled or organised so that they cannot be expanded
as they were compressed. This can reduce the memory capacity needed for development
of the state transition table to a form in which it can be referred to by the CPU.
[0081] The data compression and expansion should not be limited to specific methods and
means, but can be accomplished by, for example, an algorithm such as the Halfmann
coding or arithmetic coding or by converting the data transition table to a list structure
before the data are accumulated.
[0082] Data input/output can be made by connection of an external data processing apparatus
such as a personal computer. For this purpose, it is necessary to control line communication
features, facsimile operation buttons, and signal processing procedures and priority
of the external data input/output. These controls can be described in the state transition
table referred to above so that the program can be easily created, corrected, added,
and debugged.
[0083] If the image data are code processed before being stored in the memory of the facsimile
apparatus, the amount of codes generated by a single page changes with the nature
of the image to be processed. Therefore, the number of images which can be stored
in the memory gives capacity is variable. For the reason, it is desirable for an operator
of the facsimile apparatus to be presented with a rate or percentage of the amount
of data stored in the memory, to indicate the current state of the storage of the
image data.
[0084] In such a case, it is not always necessary that the amount of memory used is indicated
accurately, but, for example, the rate of use can be represented by one-digit number
(1 through 9) or by a other definite symbols to guide the user properly for correct
operation.
[0085] Fig. 15 is a hardware block diagram of an example of reading control. Flow line (i)
indicate data read by a reading section 2001 (corresponding to scanner 31 in Figs.
1b and 1c) and stored in a line memory 2003 through a DIPP 2002 (Product No. HD63084)
which is an image processing LSI. Flow line (ii) indicates, in turn, that image data
in the line memory 2003 is encoded by a software CODEC 2004 (ASIC in Fig.15) and is
stored in a transmitting buffer 2005. Flow line (iii), indicates that the code data
is transferred to a modem 2006 by modem interruption as transmission data in units
of eight bits.
[0086] Fig. 16 shows details of the reading section 2001. Fig. 16 shown a LED light source
2008 (corresponding to LEDS 32 in Figs. 1b and 1c) which illuminates a document to
be read. Light reflected from the document is read by a one-dimensional reading sensor
2010 provided on a preamplifier printed-wiring board 2009. The reading sensor 2010
of Fig. 16 has a CCD sensor but a MOS sensor or contact sensor may be used.
[0087] The reading sensor 2010 has a control signal given through the DIPP 2002 from a SCA
system control unit SCA 2011. The system control unit SCA 2011 also generates a turn-on
control signal for the LED light source 2008 and an interruption signal for a drive
pulse motor. The DIPP 2002 and the system control unit SCA 2011 are controlled by
a CPU 2007 (HD64180).
[0088] Fig. 17 is an image improving ASIC IPCE 2012 connected to the DIPP 2002 to improve
the image reading characteristics. The IPCE 2012 can emphasize two-dimensional edges
to prevent them from being thinned and collapsing, and can suppress moire caused during
a two-value process for a half tone image, thereby improving the image reproducibility.
[0089] As described previously, there are two modes of operation for reading a document
with the one-dimensional line sensor. One is a book reading mode in which the document
is fixed while the line sensor is moved. The other is a sheet reading mode in which
the line sensor is fixed while the sheet is moved.
[0090] Both modes of operation involve output dispersion due to shading which affects the
two-value coding of the read signal. Shading is a low frequency distortion of the
image signal when the white signal level gradually approaches te black level as the
quantity of light is lowered as the edges of the document are approached. This is
due to non-uniformity of the light source and the characteristics of the lens used
to focus the image on the sensor.
[0091] To compensate, for this distortion, the present invention makes use of the DIPP 2002.
The DIPP 2002 reads and stores reference data of one line from a white reflecting
plate 2013 in the reading section 2001 before reading the document, as shown in Fig.
18. By reference to the shading waveform, a slice level is generated to digitize the
input image data. The data of one line of the document then is read and coded to two
values using of the slice level.
[0092] First, the initial setting will be described with reference to Fig. 19 illustrating
an outline of the mechanical arrangement and Fig. 20 showing a flow chart for the
process. When the power is on, a check is made as to whether the reading section 2001
is at a center home position SHP (position A). The book reading mode makes a shading
compensation at the home position SHP (position A), while the sheet reading mode causes
the reading section 2001 to be moved to adjacent the white reflecting plate 2013 provided
near a sheet reading position, before reading starts.
[0093] If the reading section 2001 is at the home position SHP (position A), the pulse motor
is driven until the reading section 2001 moves from the home position SHP (position
A). If it does not move from the home position SHP (position A) even if more than
a predetermined number of pulses have been supplied, for example, more than 160 pulses
corresponding to 10mm of an operationable range of a detection sensor 2014 for the
home position SHP (position A), the system detects a fault and is stopped.
[0094] If the reading section 2001 moves from the home position SHP (position A) within
the predetermined number of pulses, the pulse motor drives in the opposite sense to
return the reading section 2001 to the home position SHP (position A), and the amount
of light is checked. If the amount of light is sufficient, the initial setting is
ended for the next instruction. If the quantity is too low, the operation is stopped
and a fault indicated by, for example, indicating a faulty light source.
[0095] If the reading section 2001 is not at the home position SHP (position A), the pulse
motor drives to return the reading section 2001 to the home position SHP (position
A), and the amount of light is checked. However, if the reading section 2001 cannot
be returned to the home position SHP (position A) even after a predetermined number
of pulses are supplied, for example, more than 4600 pulses corresponding to the length
of the document read, then the operation is stopped, indicating a fault.
[0096] The reading start control will now be described. Start conditions include (1) turn-on
of a transmission or copy start switch, (2) depression of a memory transmission switch,
and (3) depression of a recording switch on-hook. Condition (2) applies to a facsimile
apparatus having an image recording memory in which the read image data is written
in the memory before transmission. Condition (3) applies to a facsimile apparatus
having a feature that a destination facsimile number written on the sheet is read
before transmission.
[0097] Fig. 21 is a flow chart for the reading start operation described above. The first
step is to determine whether reading section 2001 is at the home position SHP (position
A). If it is at that position, shading compensation and the amount of light are immediately
checked. The pulse motor is driven before starting reading from a reading start position
B.
[0098] Fig. 22 is a flow chart showing the storing of the shading waveform. When the power
is turned on (step 2015), a check routine 2016 of the reading section 2001 described
in Fig. 20 is executed. The process is the same as in the book reading mode. In turn,
a check is made as to whether there is a document at the document reading position
(DET B) for sheet reading (step 2017). If not, the operation enters a waiting state
(step 2018). If there is a document it determines whether the stop is due to turn-off
of power (step 2019). If it is due to service interruption, an alarm is generated
(step 2020). If this occurs, the document is ejected (step 2021), and the operation
enters the waiting state (step 2018).
[0099] If the document to be sent arrives at a sheet reading position, a document detection
sensor DET A is turned on (step 2019). The document is pulled in until it arrives
at a document reading position DET B (steps 2020 to 2022).
[0100] In turn, the reading section 2001 moves to a shading waveform reading position (steps
2023 to 2027) at which the shading waveform is stored (step 2030).
[0101] Fig. 23 is a flow chart for both book and sheet reading modes. When the sheet reading
document detection sensor DET A is turned on in the waiting state (step 2018), as
described in Fig. 22, the document is drawn in, and the shading waveform is stored
(steps 2020 through 2030). The LED light source 2008 then is lit (step 2031). For
the two-value, a peak value of the image signal is generated (step 2030) to make an
optimum image determination reference to read. For a half tone, a dither pattern is
set as a pseudo tone pattern corresponding to the tone (step 2033), the slice level
for the image signal is written (step 2034), and reading starts.
[0102] When reading a document, there may be e.g. three reading pitches in a sub-scanning
direction, including 3.85 line/mm, 7.7 line/mm, and 15.4 line/mm. The standard mode
is 3.85 line/mm. The drive motor usually used is a pulse motor. If the step number
is 4 pulse/line for the 3.85 line/mm reading pitch, for example, it is 2 pulse/line
and 1 pulse/line for the 7.7 and 15.4 line/mm pitches, respectively. To keep the reading
time per line constant, the speed of the pulse motor for the 3.85 line/mm reading
pitch is made 400 pps (pulses per second).
[0103] On the other hand, since the quantity of light must be constant, the speeds for the
7.7 and 15.4 line/mm are 200 and 100 pps, respectively. At 3.85 line/mm, the pulse
motor needs the highest drive torque. If the drive torque is sufficient, constant
movement is possible from the outset, but such a motor costs too such to be economic.
For this reason, smoothing occurs so that the motor speed is gradually accelerated
to 200, 300, or 400 pps.
[0104] The operation described above applies to both book and sheet reading modes as the
relative distance between the document and the reading sensor is the same.
[0105] Fig. 24 shows the relationship between the motor speed and data storage in an image
storage line memory 2035 for the 3.85 line/mm reading pitch. Reading starts from point
A and is accelerated. The motor speed of 300 pps is an example for which feeding of
three lines is made because of low reading timing drive torque, which will be described
later, and then enters the reading operation 400 pps drive.
[0106] When the encoding speed is slow as compared with the reading speed or when the line
communication speed is slower than the encoding speed, data storage in the image storage
line memory 2035 is increased. As the image storage line memory 2035 has a limited
capacity however, reading must halt when a certain amount of data has been stored,
In Fig. 24, read halts with the motor speed slowed down to 300 and 200 pps when the
data representing 218 lines have been stored. When the data in the image storage line
memory 2035 data in the image storage line memory 2035 decreases as the data transference
continues, the reading starts again by accelerating the motor.
[0107] The relationship between data storage in the image storage line memory 2035 and reading
is identical for the 7.7 and 15.4 line/mm reading pitches except that, if no motor
acceleration is necessary, the smoothing which allows immediate start at a predetermined
speed is not needed. For example, Figs. 25 and 26 show the relationships between the
motor speed and data storage in the image storage line memory 2035 for 7.7 and 15.4
line/mm reading pitches, respectively.
[0108] Fig. 27 shows the relationship between the pulse motor and reading control during
the smoothing process. Fig. 27(a) shows the sequence of change from a constant reading
speed to stopping of the pulse motor, and Fig. 27(b) shows the sequence when reading
starts or is re-started after a short stoppage. Figs. 27(a) and 27(b) indicate storage
times per line, 10 msec for 400 pps, 13.3 msec for 300 pps, and 20 msec for 200 pps.
[0109] As the storage time per line is changed, as mentioned above, the amount of light
at a 200 pps pitch is twice that at a 400 pps pitch if it is not changed. To avoid
this, the LED light source 2008 is made to blink (pulse) so that the amount of light
can be equal at any speed of the pulse motor. The sensor output signal obtained as
described above is transferred from the DIPP 2002 by DMA (direct memory access). Reading
can be made stable, by synchronization with the interruption of the pulse motor from
the system control unit SCA 2011.
[0110] The DMA transference does not occur when the pulse motor is halted, as shown in Fig.
27(a), but is synchronized with the start of the driving of the pulse motor, as shown
in Fig. 27(b).
[0111] It is possible to use a reading method that the storage time per line is constant,
and have not related to the motor speed. This method, however, is not desirable as
the un-synchronization causes differences between the document movement and read range,
resulting in an adverse affect on the image quality.
[0112] To cause the LED light source 2008 to pulse, a turn-on control signal may be fed
from the system control unit SCA 2011 to a switching transistor Q1 as shown in Fig.
28. Fig. 28 also shows limit resistors RA and RB.
[0113] With the arrangements described above, the amount of light can be controlled so as
to be constant even if the storage time is changed in dependence on the pulse motor
speed.
[0114] It is also possible to use pulsing to reduce the reading size. In the following example,
a B4 image is reduced to A4. For this, the line density has to be reduced to 5/6,
or the image of six lines has to be reduced to that of five lines.
[0115] Fig. 29 is the sequence diagram of the motor speed at reading timing and LED control
for a 3.85 line/mm reading pitch. Lines 3 and 5, after conversion, have an original
image of 1.5 lines each as shown, thereby preventing the image quality from deteriorating.
For this purpose, the read timing pulse TSCAN is extended to 1.5 times at line 2 after
reading, at the same time, the turn-on time of the LED light source is reduced to
1/1.5, and lines 3 and 4 are read. The next read timing pulse TSCAN is returned to
the original pulse duration, and the line 5 is read. Such operations are cyclically
repeated so that size conversion can be accomplished.
[0116] Fig. 30 is the sequence diagram for a smoothing process for a 3.85 line/mm reading
pitch. Phases (a) to (e) in Fig. 30 show that control is changed at lines 3 and 5.
The interruption signal can be generated even at a stoppage by generating a dummy
interruption signal. Phase (a) shows that line 3 overlaps the 300 and 400 pps pulse
motor speeds where the amount of light at each of the pulse motor speeds is reduced
to 1/1.5 from the last period of 400 pps to stop. Phases (d) and (e) show that the
amount of light is reduced after stoppage of the motor.
[0117] Phases (b) and (c) show that control has to be made to avoid image deterioration
due to a stoppage during operation. For this purpose, as the time of stoppage of the
pulse motor can be predicted in advance by checking the image accumulation line memory
2035, phase (b) may have the amount of light reduced to 1/1.5 at the same timing as
phase (a). That is, lines 2 and 3 are controlled. Similarly, phase (c) is made to
have the same timing as phase (d). In this way, optimization can be made.
[0118] Fig. 31 is another embodiment which can solve the complication of the control arrangement
described above. Line 3 is an average of the preceding lines 3 and 4. The reading
time on line 3 is extended twice, while the LED turn-on time is halved. Line 4 onward
again has a normal reading time. This needs only a change in the TSCAN and the LED
turn-on time at the same time so that the control can be simplified significantly.
[0119] Also, the smoothing process has no problem as only the storage time and the LED turn-on
time are to be by two lines even if the pulse motor speed changes during operation.
However, the situation of line 3 at a 200 pps switch which causes stoppage, resulting
in image deterioration. This has to be avoided. Its control can be easily made as
the image storage line memory 2035 is being monitored.
[0120] As described above, the present invention can vary the reading time as the pulse
motor is controlled and at the same time, can change the amount of light so that a
predetermined amount of light can arrive at the reading sensor at all times, thereby
ensuring a good quality image.